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formation of Khwārezm-Shāh empire

...the Khwārezm-Shāh ʿAlāʾ ad-Dīn Tekish was one of many contenders in a struggle for supremacy in Iran. By 1200 the Khwārezm-Shāh had emerged victorious. ʿAlāʾ ad-Dīn Muḥammad (reigned 1200–20), the penultimate Khwārezm-Shāh, created a short-lived empire that stretched from the borders of India to those...

history of

Afghanistan

Shortly after Muḥammad of Ghūr’s death, the Ghurīd empire fell apart, and Afghanistan was occupied by Sultan
ʿAlāʾ al-Dīn Muḥammad, the Khwārezm-Shah. The territories of the Khwārezm-Shah dynasty extended from Chinese Turkistan in the east to the borders of Iraq in the west.

Central Asia

...Darya and threatened Khwārezm, located in the Amu Darya delta. However, their hold on this vast domain was finally shattered in 1211, through the combined actions of the Khwārezm-Shah
ʿAlāʾ al-Dīn Muḥammad (1200–20) and Küchlüg Khan, a fugitive Naiman chieftain in flight from Genghis Khan’s Mongols.

Iran

The collapse of the Karakitai empire northeast of the Oxus was partly accelerated by the unsuccessful bid of Khwārezm-Shah
ʿAlāʾ al-Dīn Muḥammad (reigned 1200–20) to win Muslim approval while releasing himself from the Khwārezm-Shahs’ humiliating tributary status to an infidel power. But the coup de grâce to the Karakitai empire was...

Iraq

...from the caliph a few years later, al-Nāṣir refused, and inconclusive fighting broke out between the two. The conflict came to a head under Tekish’s son, the Khwārezm-Shah
ʿAlāʾ al-Dīn Muḥammad (1200–20), who demanded that the caliph renounce the temporal power built up by the later ʿAbbāsids after the decline of the Iraq...

opposition to Mongol expansion

...campaigns were set in motion quite accidentally by a senseless attack on Mongol forces by the fugitive Naiman prince Küchlüg, and they maintained their momentum through the pursuit of
ʿAlāʾ al-Dīn Muḥammad of Khwārezm, who in 1218 ordered the execution of Mongol envoys seeking to establish trade relations.

The first Mongol incursions into Islamdom in 1220 were a response to a challenge from the Khwārezm-Shāh
ʿAlāʾ al-Dīn Muḥammad, the aggressive reigning leader of a dynasty formed in the Oxus Delta by a local governor who had rebelled against the Seljuq regime in Khorāsān. Under Genghis Khan’s leadership, Mongol forces destroyed numerous...